Multiferroic triphase BFO-PZT-PVDF composite with significant magnetoelectric response for multistate device applications

Abstract

Triphase multiferroic composites with higher degree of freedom, provide a new platform for developing novel and smart technological applications. In this context, here we present a new triphase composite, consisting of bismuth ferrite (BFO) and lead zirconate titanate (PZT) synthesized using sol‒gel auto-combustion and solid-state routes, respectively and then subsequently dispersed into a PVDF polymatrix, leading to a triphase composite (BFO-PZT-PVDF). Structural analysis confirmed the composite formation as all the intensity peaks were either matched with BFO or PZT phases. Morphological analysis revealed that pure BFO and PZT formed well defined grains with sharp grain boundaries. However, when they are dispersed in the polymer matrix, their boundaries became diffused. Worth mentioning ferroelectric parameters like saturation polarization, remanent and recoverable energy density are measured from bipolar polarization loops. It is noticed that maximum polarization is decreased while coercivity is increased with the increment of PZT contents in the composite. Vibrating sample magnetometer confirmed the variation in magnetic features, exactly in accordance as required for significant magnetoelectric coupling for practical utilization. The extent of magnetoelectric coupling supports the potential applications of these triphase composites for energy storage and multistate devices.